1. Field of the Invention:
The present invention relates to a copying machine and, more specifically, to a copying machine incorporating a copying system capable of successively copying two different documents, such as the successive pages of an open book, on two different recording medium surfaces.
2. Description of the Prior Art
Recently, an electrophotographic copying machine, such as disclosed in U.S. Pat. No. 4,017,173, incorporating a copying system capable of successively copying two different documents on two different recording medium surfaces has been proposed to improve the efficiency of copying operation. In such a copying machine, the successive pages of an open book placed on the contact glass are scanned successively and are copied on the respective surfaces of two separate copying sheets or on the opposite sides of a single copying sheet in a single copying cycle. Accordingly, copying sheets need not be cut in a predetermined size, and hence such a copying machine is capable of efficient copying operation.
However, the conventional copying machine incorporating such a copying system is merely capable of successively copying different documents in the same copying conditions.
As regards copied image density, one of the copying conditions, for example, in copying the successive pages of an open book placed on the contact glass in a single copying cycle, the copying machine is unable to be set in two different copying conditions appropriate to the different pages, respectively. Therefore, when the two pages are different from each other in original image density, one or both of the pages are not copied in a desired copied image density. Such a problem arises also in successively copying two different documents different from each other in original image density in a single copying cycle.
As regards copying magnification, another copying condition, in successively copying two documents different from each other in size in a single copying cycle, the sizes of the respective copied images of the two documents are different from each other, because the conventional copying machine is unable to be set in different copying magnifications for the two documents, and hence it is impossible to obtain the copies of the same image size from documents different from each other in size.